“The planes were flying over these areas of intelligence and geopolitical interest — things like airfields in the middle of nowhere in Syria,” said Emily Hammer, who co-authored the study. “But they passed over a lot of other places on their way to their main targets, and they had their cameras on while they were doing that.”

The spy planes were equipped with high-resolution cameras which were able to capture crystal clear images despite flying at altitudes of 70,000 feet, which is nearly twice as high as the cruising altitude of commercial airplanes.

Hammer worked with Harvard anthropologist Jason Ur to digitize the original film strips from 11 different U-2 missions that were flown over the Middle East during the 1950s and 1960s. The film strips were not indexed which made it difficult for them to recreate the flight paths of the planes so they could pinpoint the locations of their discoveries.

"These case studies include investigations of prehistoric mass-kill hunting traps in eastern Jordan, irrigation systems of the first millennium BC Neo-Assyrian Empire in northern Iraq, and twentieth-century marsh communities in southern Iraq," they explained in the study which was published in the Advances in Archaeological Practice.

Hammer says the photographs are important because they detail historical sites that have been destroyed over the past seventy years.

“What we see in these photographs is no longer there, which is the case with archaeological sites, but more critically and more tragically, these images preserve a record of a place like Aleppo that has been completely destroyed just in the last 10 years by the Syrian civil war,” Hammer said. “So it’s not just about the deep past, but it’s also about accessing something that was very recently there but is no longer.”